Until my friend Chris Carter, classical scholar and self-confessed word junkie, pointed it out in an email this morning, I hadn't realised that the humorous definitions with which Chambers Dictionary is sprinkled, are so much a part of the publishers' culture. He gave as an example the noun "bafflegab" and the definition according to Chambers; adding that 'such mischievous wit is intentional and sporadic throughout Chambers, a tradition maintained from the earliest days.'
'Bafflegab (slang) the professional loggorhoea of many politicians, officials, and salespeople, characterized by prolix abstract circumlocution and/or a profusion of abstruse technical terminology, used as a means of persuasion, pacification, or obfuscation.'
I dug around a little and came up with this example from the various meanings of the word 'pet':'Pet (inf) to indulge in amorous caressing. [Origin unknown; not from Gaelic]'